[dragonwriter]

If you mean on TV, I think from the dawn of TV virtually no sci fi being made has been pretty much the norm. (Unless you use a broad enough definition that that wouldn't be true, even excluding ST:TNG, of the early 1990s, either.)

[lmm]

I think there's still a distinct dip in the '90s. In the '80s we have the last gasp of Dr Who, we have The Tripods, V, Day of the Triffids, and a bunch of one-off adaptations. In the '00s we have big remakes of Dr Who and Battlestar Galactica (hell, even V), or the aforemaligned Dollhouse which for all its flaws was more willing to engage with sci-fi themes than, I dunno, Quantum Leap.

I've neglected Babylon 5, which is probably unfair to the show, but I feel like it never had the cultural impact of those '80s or '00s shows. The '90s drought feels real to me, but maybe it's just a matter of perception.

[dragonwriter]

I suspect this is more a matter of what "sci fi" you like. The 1990s had lots of sci fi TV shows, including, among others:

X-Files

SeaQuest DSV / SeaQuest 2032

More Star Trek than you can shake a stick at (TNG, DS9, and VOY cover the whole decade, with most of it having two at once)

Babylon 5

Sliders

Stargate SG-1

Farscape

I think there's a better case that the 1990s were the high-point of sci fi popularity on TV than a particular drought (though I can see a case that there was something of a drought starting sometime in the mid-1980s through 1993.)

[existencebox]

You (and parent posts) leave out a few important mentions. SG1, of course; but then some more b-rate but still watchable shows like Andromeda. Stargate at least had some sort of impact, I like to think.